USA Online Slots

Online Slots can be found at almost all online casinos. In terms of games selection, it’s the virtual slot machines offered which represent the main differences in game selection.

Casino sites offer hundreds of slot games with a myriad of different features. Games are touted for their features, so this slots guide helps beginners make sense of it all.

Our OUSC guide provides basic tips to play online slots, shows you how to choose a game, details the types of slots and features, briefly goes over the history of slot machines, and ends with a section of frequently asked questions. Once you finish reading, you should have a basic understanding of how online slot machines work.

Best Online Casino Slots  2018 

#1 Ranked Online Casino Site

  • 1
    BetOnline Casino
    • Accepts US Players, Highly Recommened
    • Online, Download, Live, & Mobile Casino
    • Over 100 Casino Games
    Deposit Options include:
    • visa
    • mastercard
    • skrill
    • bitcoin
    Compatible with:
    • windows
    • apple
    • mobile
    100% up to $1,000
  • 2
    • Accepts US Players, Highly Recommened
    • Online, Download, Live, & Mobile Casino
    • Over 100 Casino Games
    Deposit Options include:
    • visa
    • mastercard
    • bitcoin
    Compatible with:
    • windows
    • apple
    • mobile
    75% up to $1,000
  • 2
    Cafe Casino
    • US Accepted & Apple Mobile-friendly
    • Big Bonuses and Over 330 Casino Games
    Deposit Options include:
    • visa
    • mastercard
    • debit
    • bitcoin
    Compatible with:
    • windows
    • apple
    • mobile
    500% up to $5,000
  • 3
    Bovada Casino
    • Top Mobile Casino
    • US Players Welcome
    • Live Baccarat, Blackjack, Roulette & Super 6
    Deposit Options include:
    • visa
    • mastercard
    • bitcoin
    Compatible with:
    • windows
    • apple
    • mobile
    100% up to $3,000
  • 3
    Las Vegas USA
    • Great Selection of Instant Play Games
    • Variety of Bonuses for Tables Games
    Deposit Options include:
    • visa
    • mastercard
    • neteller
    • bitcoin
    Compatible with:
    • windows
    • apple
    • mobile
    200% up to $5,000
  • 3
    Betway Casino
    • Uses the Microgaming Software
    • Fast Cashouts in Just 1-7 Days
    • Online, Mobile, Instant & Live Play
    Deposit Options include:
    • visa
    • mastercard
    • paypal
    • neteller
    Compatible with:
    • windows
    • apple
    • mobile
    100% up to $1,000
    100% up to €1,000
    100% up to £1,000
  • 3
    888 Casino
    • Operating in Good Standing Since 1997
    • Great Graphics and Sounds that are Updated Frequently
    • Fast and Secure Credit Card Deposits
    Deposit Options include:
    • visa
    • mastercard
    • paypal
    • neteller
    Compatible with:
    • windows
    • apple
    • mobile
    100% up to $200
    100% up to €140
    100% up to £100
  • 3
    Spin Palace
    • Premium 24 Hour Live Support
    • Biggest Progressive Jackpots
    • Safe and Trustworthy Deposit Options
    Deposit Options include:
    • visa
    • mastercard
    • paypal
    • bitcoin
    Compatible with:
    100% up to $1,000
    100% up to €1,000
    100% up to £1,000
  • 3
    Jackpot Casino
    • Big Jackpots and Massive Deposit Bonuses
    • Over 400 Online Casino Games
    • Play Live Dealer Games
    Deposit Options include:
    • visa
    • mastercard
    • paypal
    • bitcoin
    Compatible with:
    • windows
    • apple
    • mobile
    100% up to $1,600
    100% up to €1,600
    100% up to £1,600
  • 3
    • Large Australian Bitcoin-Friendly Casino
    • Mobile, Flash, and Download Play Options
    • Fastest Payouts
    Deposit Options include:
    • visa
    • mastercard
    • paypal
    • neteller
    Compatible with:
    • windows
    • apple
    • mobile
    200% up to $1,000
  • 3
    Fair Go Casino
    • Safe and Trustworthy Australian Casino
    • Mulitple Daily Deposit Deals
    • 100s of Pokies, Slots, and Table Games
    Deposit Options include:
    • visa
    • mastercard
    • wire
    • bitcoin
    Compatible with:
    • windows
    • apple
    • mobile
    • linux
    100% up to $1,000

Basic Tips for Online Slots

These are a few basic ideas about gambling that can be useful to new online slot players.


No long-term profits

The house edge gives the casino the advantage on virtually every bet. Over time, the house edge assures that players lose more money than they win. Imagine betting someone on the results of a coin toss. If you win, you pay $50. If the opponent wins, they pay $45. Over time, you’ll lose money on this proposition.


Max bet is the best bet

There are basic ways you can increase your odds of winning in USA online slots. Making the maximum bet is generally the way to get the best payout. Taking advantage of the welcome bonuses and reloads also helps. Many websites now offer slot-specific bonuses and these should be tapped every chance you get.


Visit Several Online Casinos to Recieve Better Odds

Shopping around for online slots in the USA is the best way to find better odds or a better experience. You don’t have to buy everywhere, but shop around by doing research and you will eventually find the best online casino. To find out about more helpful suggestions and tricks, make sure to read our tips for playing slots page.

Top 4 USA Online Slots Casinos

United States online slots casinos offer large welcome bonuses, along with massive slots-only bonuses. USA-friendly sites support the U.S. dollar and English language, while most have VIP rewards clubs for loyal players. These USA online slots casinos support the most common forms of payment, including Visa, MasterCard, American Express, and Bitcoin. When it’s time to withdraw, they make smooth transfers to American banks and credit card services.

Slots LV Casino Casino Complete List of Slot Games

Click Image to Expand

Read Review is a USA online slots casino where new players can get up to $5,000 in Welcome Bonuses, because players receive bonus money on their first nine deposits.

  • They offer more than 190 Slot Games from the top software companies.
  • Enjoy a 8-tier rewards program called MySlotsRewards.

All games at Slots LV use Real Time Gaming, Rival, and Betsoft software, so players receive a wide variety of the best online slots in the USA gaming market.

Play any of the hundreds of slot games and titles at the incredible Casino, where they offer you the ultimate Las Vegas experience!

International Online Slots Casinos

International slots casinos accept players from most countries outside the United States. The software companies which support real money online slots receive support from brands like NetEnt, Microgaming, and Playtech. This provides a wider variety of slots titles, including the most famous licensed slots, the biggest progressive jackpots, and the most advanced cinematic 3D slots. Players can expect to encounter a wide variety of deposit methods and licensing authorities.

888 Casino is the international slots casino supported by 888 Holdings, a global company listed on the London Stock Exchange.

888casino offers a £/$/€1,500 welcome bonus on deposits using Visa, MasterCard, PayPal, and a variety of other payment methods.

Popular companies like NetEnt, IGT, WSM Interactive, and Next Gen Gaming support 888’s video slots selection.

How to Choose a Slots Game

Once you get to slots row, you might find the selection process confusing. Below is a how-to guide on choosing the perfect USA Online Slot game. We divide slots into two sections: those with the highest payout percentage and those with the biggest jackpots.

Highest Payout Percentage

  • One method for choosing USA online slots is to find the highest payout percentage. This is easier said than done, because most casino operators would prefer to keep their payouts a mystery. We can put these games in categories, though, according to jackpots, signage, and coin denominations.
  • Classic 3-Reel Slots

    As a general rule, the best USA online slots with a fixed jackpot have a higher payout percentage. If you’re new to slots row and wonder why some gamblers camp out on 3-reel classics like “Red White & Blue” or the “777” slot machines, it’s because they have high fixed jackpots. Essentially, those gamblers know they’re getting a better deal with these than the progressive players.

    Along the same lines, slot machines with smaller screen, fewer graphics, or less “entertainment value” have higher payout rates. The idea is that good USA online slots don’t have to advertise as much. Also, designers and casino owners would prefer that players search for the better machines.

  • Higher Denomination

    High rollers get better deals. As a general rule, the bigger the coin denomination, the lower the house edge. Casino owners want to encourage high stakes players to gamble at their venue, so they offer better payout rates to premium players and high rollers.

    If you want the highest payout percentage, look for the online slot games with fixed jackpots, little fanfare, and the highest coin denominations you can afford. Do not wager more of your bankroll than you can stand to lose comfortably. If you overspend to get better odds, you’re making a bad financial decision.

  • Max Bets

    Players who prefer the highest payouts often wonder whether to place the max bets. Most USA online slots encourage players to make the max bet by offering a bigger jackpot on the max bet. This is the “economy of scale”, where the cost goes down as the numbers increase. On the other hand, casinos increase the theoretical return when the coin denomination is higher. If the jackpot pays out a higher percentage, make the max bet. If not, then lower your coins wagered and increase the denomination.

Largest Jackpot

  • Progressive slot machines are going to be the games with the largest jackpots. A progressive jackpot accumulates over time. Each spin which does not trigger the progressive feeds the pot by a little bit more. Progressive jackpot slots can be any size, but the most famous ones range into the millions (or tens of millions) of dollars.
  • MegaBucks

    MegaBucks holds 80% of the Top 10 slots jackpots in gambling history. When you hit a MegaBucks progressive jackpot, it’s going to pay out anywhere between $10 million and $40 million. This has spawned a whole array of imitators, which usually have the word “Mega” in the name. Examples include Megasaur, Mega Moolah, MegaJackpots Monopoly 3 Progressive, MegaJackpots Cleopatra Progressive, and MegaJackpots Cluedo Progressive. If it has “Mega” in the title, it’s likely to be one of the largest jackpots in the casino.

  • Other Progressive Slots

    That being said, many other fine progressive slot machines exist. Wheel of Fortune Slots from IGT pays out over forty $1 million-plus jackpots every year in Nevada alone. These are not the biggest prizes in the industry, but it is the most popular game, because it offers a high frequency of hits. Of this particular licensed brand, Wheel of Fortune Super Spin has the highest jackpot.

    Analysts like me have mentioned many times that the progressives have some of the lower return rate among the slot machines. It doesn’t matter. Players love the progressives. Gamblers play the lottery for the same reason: the idea of hitting a life-changing jackpot.

Types of Online Slots

Below is a description of the types of games you’ll find at the best USA online slots casinos. A slot machine might be described as two or more of the sub-types listed below. For instance, a video slot might be a progressive slot and an interactive slot. We offer the definition of each, so you’ll know what’s being described.

Video slots

Video Slots

A generic term for any online slot machine, because it requires a video screen to play it. The term developed from the land-based video slots, which were roughly synonymous with electronic slot machines. In today’s terms, it usually refers to a game which has 5 reels, multiple paylines, bonus features, and video clips.

licensed slots

Licensed Slots

Slot designers sometimes design a game based on popular franchises from the movie, TV, music, or other pop culture industries. Licensed slots have been based on comic books, novels, sports, board games, or monthly magazines. Because of the audio and visual clips needed, these are video slots.

interactive slots

Interactive Slots

Interactive slots or iSlots are games which have an interactive bonus game. The player interacts with the game. Essentially, you make a decision and its affects the outcome of the game. All interactive slots are video slots though all video slots are not interactive.

3D slots

3D Animated Slots

Video slots which use 3D animations for cut scenes and bonus games. These have the best graphics of any slot machine. The designers are trying to develop video game-level graphics and have succeeded. Net Entertainment and Sheriff Gaming have advanced 3D slots.

skill-based slots

Skill-Based Slots

Speaking of video games, slot machines with skill elements are meant to mimic the player experience of a video game or online game. In fact, skill slots are going to offer bonus games with licensed games like Angry Birds, Words With Friends, Pac-Man, Space Invaders, and Guitar Hero. These are not in casinos yet (and not online), but have been approved by Nevada, New Jersey, and Massachusetts. When they appear in casinos, it won’t be long before they appear in online and mobile casinos.

Online Slots Jackpots

Jackpot is a loaded word in slots these days, because of all the different kinds of jackpots available. So let’s look at the various jackpots that you’ll find at USA online slots casinos, as well as what they offer.

Fixed Jackpots

Progressive jackpotMany slots have fixed jackpots, meaning the value always stays the same regardless of when the last time the jackpot was won. Most fixed jackpots are only worth between 5,000 and 10,000 credits, which means they aren’t usually big draws.

Progressive Jackpots

progressive jackpot slotsThese jackpots grow with every qualifying bet that’s made and will keep growing until somebody wins. No other feature has more attractive power than the progressive jackpot. Gamblers play these games, even though they know the progressive slots have a higher house edge. The reason is the same reason people play the lottery: they get a chance at a life-changing jackpot.

The majority of progressive jackpots are only worth around $8,000 to $20,000. But some jackpots, like the Mega Moolah (online) or Megabucks (land based) prizes, can be worth millions of dollars.

Obviously, it’s exciting to think about playing for this kind of cash. But keep in mind that you often have to make a $1 side bet in addition to your original stake to qualify.

Random Progressive Jackpots

megamoolah slotsAlmost every type of USA online slots jackpot is hit through a certain winning combination. A random progressive jackpot, on the other hand, can be hit on any spin, regardless of your spin result or bet size.

While you normally don’t have to make a side bet or wager a certain amount, you have a better chance of winning the random progressive jackpot by making a higher bet.

Even still, these prizes offer additional excitement for players who can’t afford to play a Mega Moolah or Megabucks type game.

Multi-level Jackpots

forrest gump slotsIGT has been introducing multi-level progressive jackpots in the last few years. The typical way these work is a 5-in-1 progressive jackpot system. The lowest-level progressive might be a $10 jackpot. The next level might be a $50 prize. The next progressive might be worth $100 to $200 while the fourth level might be worth $500 to $1,000.

These are independent of each other though one might feed into the other. That is, these prizes might work like the “Multi-Level Pick a Box” bonus feature, where winning one prize might allow you to advance to the next progressive level. In most cases, whether it’s a 4-in-1 or 5-in-1 progressive, the machine also offers the big progressive, which is worth 6-figure or 7-figure amounts and is 100% independent of the others.

Games like Amaya’s Forrest Gump and Daub Games’ Grease offer multi-level jackpots, meaning there are actually several jackpots rolled into one. For example, Grease has you scratch off spaces on a card, and the first four jackpot spaces that you reveal determines if you’ll collect the small, medium, big or top jackpot.

Local Area Progressives

Local Area progressivesLand-based casinos offer linked or networked slot machines. Like the Internet networks multiple computers together, the link progressive jackpot links together slot machines for the sake of feeding the same pot. This allows a machine’s jackpot to grow faster and larger. The local area networked progressive tends to be all the machines in a bank of games, or all on one slots row. The biggest jackpots exist on the wide-area progressive network.

Wide Area Progressives

Wide area progressivesBrick-and-mortar casinos offer some slot machines which are linked to slots in other casinos, often in other states or countries. These are the wide-area progressives, which grow the fastest and biggest of all. The MegaBucks Slots network is a good example of this. Every MegaBucks slot machine in the State of Nevada feeds into the same pot until someone wins the prize.

Online Slots Reels

The number of reels in a slot machine is important because this greatly affects how many winning combinations and features a game can offer. Up until the 1970s, all slots were 3 reel games that operated on mechanical reels.

But ever since the Fortune Coin Co. developed the first video slot in 1976, manufacturers have been able to add more reels, thus increasing the number of slots features. Below you can see what to expect from the varying reel amounts at USA online slots.

3 Reel Slots

3 reel slotsSometimes referred to as classic slots, 3 reel games are usually among the most basic that you’ll find in USA online slots. True classic slot machines only offer one pay line and typically have no special slot features beyond a fixed jackpot.

The main reasons to play these games are if you’re just learning slots or if you’re nostalgic for old Vegas trips.

However, do note that you can find 3 reel slots with decent features and/or innovative concepts. Betsoft’s Ghouls Gold is one that we can think of because it has three different 3 reelers stacked on top of each other, with the first 3 reel set unlocking the above games.

5 Reel Slots

5 reel slotsThe best and most popular online slots USA are almost always found in this category. 5 reel slot machines seem to strike the perfect balance between offering enough different payout combinations and slots features without overloading the player (see 7 reels).

Based on the popularity of 5 reel slots, you’ll see the biggest progressive jackpots offered through these games. You’ll also find that most of the latest USA online slots releases have 5 reels.

So unless you’re looking for a simplistic slots experience, like what you’ll find with 3 reelers, we suggest that you begin with 5 reels.

6 Reel Slots

6 reel slotsAmong the features of online slots in the USA, a very small percentage of slot machines have 6 reels. This isn’t to say that 6 reel slots are inferior to 5 reel games, but as far as slots features, this variation is just not very popular.

Perhaps the reason why is because with an extra reel involved, these games leave less room on the side for background/theme artwork. Nevertheless, these slots can be just as fun as 5 reel slots since they offer good features and lots of payout combinations.

Examples of 6 reel slots include NetEnt’s Aloha! Cluster Pays and Realtime Gaming’s Lucky 6.

7 Reel Slots

7 reel slots7 reels is one of the slots features that never took off. We don’t know of any 7 reel slot machines in land-based casinos, and there are only a small number of online slots in the USA with this many reels.

A couple of 7 reel slots examples include Barcrest’s Jackpot Jewels and Wager Gaming’s Lucky 7’s.

The good thing about 7 reel games is that they give players numerous pay line combinations. The downsides include that there’s absolutely no room on the side for background graphics, and some players may feel overwhelmed with so many possible payouts.

Other Slots Styles

jenga slotsFew examples exist of developers going outside the traditional reel model when creating slots. However, Amaya’s recent Jenga slots game takes a different approach.

These USA online slots features can be considered a different game entirely, but rely on the same concept. Instead of having reels, Jenga is just like the Parker Brothers’ game in that it’s a tower shaped slot. Each level of blocks is considered a pay line, totaling 18 pay lines in all.

The main problem with Jenga is that it doesn’t offer much beyond the unique tower shape and good graphics. Nevertheless, it’s an interesting approach that other companies may expand on in the future.

Paylines in Online Slots

As discussed before, the earliest 3 reel slot machines only had one pay line. However, as slots features evolved, so did the number of paylines, to the point where some slots have dozens or even hundreds of paylines.

Here’s what you can expect from USA slots online, based on the number of paylines that they have.

Single Payline

single paylinesThis is the oldest and most basic model that you’ll find in USA online slots, and single pay line games don’t offer many, if any, special features.

You must land symbols directly in the center reel for a winning payout in single pay line games.

The online slots in the USA are usually pretty cheap to play because you only use 1 3 coins per bet. In most cases, it’s to your advantage to play all 3 coins because there will be a favorable jackpot progression on a 3 coin bet.

Many players will find single pay line games boring after a short while because they just don’t offer enough extra frills.

20 to 30 Paylines

20 to 30 paylinesThis seems to be the sweet spot of online slots USA features for most players, especially since many 5 reel games feature 20, 25 or 30 paylines.

The nice thing about this range of pay lines is that you have more chances to win without spending a fortune to play.

Some 20 to 30 pay line slot machines force you to play every pay line while others let you adjust the amount down to just one pay line. But even when you’re forced to play every pay line, you can keep the coin size at one cent and only bet between $0.20 and $0.30 per spin.

We recommend the games with this feature because they improve the number of times that you’ll win and keep things more entertaining. But if you’re ever confused by how all the different paylines work, just click the help screen and you’ll be shown the different line combinations.

243 Ways to Win

dark knight rises slotsIf you’re used to traditional USA online slots, you know that many of them only pay when symbols line up from left to right in an active pay line. However, a 243 ways game eliminates paylines and instead allows pay lines to be created as long as they’re in adjacent reels.

For example, the same symbol anywhere on reels 1, 2, and 3 could form a winning payout. If you’re familiar with scatter symbols, which we’ll discuss later, a 243 ways to win game basically makes any symbol a scatter. This make it one of the most enticing slots features available.

Examples of 243 ways slots include Microgaming’s The Dark Knight Rises, Immortal Romance, and Thunderstruck.

These USA online slots can certainly make for exciting play because you have a good chance to win on any spin. But the only downside is that it can be one of the slots features with the highest betting requirements. You usually have to bet at least $0.25 to $0.50 per spin, which might make low rollers uncomfortable.

1,024 Ways to Win

1024 ways to winThese are the same concept as 243 ways slots, except that they feature 5 reels that are four spaces high (5×4 grid), instead of the traditional 5×3 grid.

This extra space above each of the 5 reels helps create 1,024 ways to win. Examples of games with this slots feature include Aristocrat’s Buffalo and Wicked Winnings III.

Just like the 243 ways games, these slots create additional excitement with the potential for many different payouts. But again, compared to other slots features, the minimum spin cost will be higher than most games.

Online Slots Bonus Features

USA online slots have bonus features programmed into them to increase their entertainment value. Bonus games offer animated cut scenes, music, and audio clips, but the features below affect the game mechanics and odds. When a bonus feature is encountered, it gives players a sense of accomplishment and the idea that something special is about to happen. Below you can get an overview of the most common. Additionally, if you feel like some terminology is confusing, make sure to check out the slots terms page.

 free spins slots

Free Spins

The most basic bonus that you’ll earn in USA online slots is free spins. These are often triggered by scatters and theoretically give you a chance to spin the reels for free.

Some free spins also come with a multiplier, which helps you net bigger payouts. But even when a multiplier is involved, free spins are one of the blander slots bonuses.

 second screen bonus slots

Second Screen Bonus

These are the most appealing types of slots bonuses because they take you off the reels and into a different setting.

At the best USA online slots you’ll find all sorts of second screen bonus rounds like selecting positions on a treasure map, spinning a wheel, choosing what direction a character goes, guessing whether a number will be high or low, and randomly selecting items.

Some land based slot machines, like those by Bally Technologies, even offer interactive technology where you touch the screen to spin a wheel (U-Spin).

This variety is part of what makes second screen bonuses so fun because you never know what a game will offer until you start playing (or look at the help screen). And even the simple bonus games that merely involve spinning a wheel or selecting items can be fun.

So we highly recommend any slots you can find with second screen bonuses.

 Wild slot symbol

Wild Symbols

The wild symbol is one of the most common features in the best USA online slots. Wild icons substitute for any other icon on the reel to complete winning combinations (with certain exceptions). For instance, wilds usually substitute for all symbols, except the scatter symbols. The wild symbol increases a player’s odds of hitting a winning combination, making this a fan favorite. Several types of wilds exist: common ones are cascading wilds, expanding wilds, and stacked wilds.

 Expanding Wild

Expanding Wild

An expanding wild symbol expands to cover an entire reel. If you’re playing on the standard 5×4 screen, then an expanding wild expands to cover all 4 symbols on that particular reel. This is popular because it increases fourfold your chances of hitting a winning combination with the wild icon.

 Shifting Wild

Shifting Wilds

Also called a “symbol slide”, this is similar to the expanding wild, except the wild symbols expand horizontally instead of vertically. If you have a 5×4 screen and a shifting wild appears as the top symbol on the 3rd reel, then the top icon on all 5 reels would become wild.

 Cascading Wilds

Cascading Wilds

A cascading wild is sometimes confused with an expanding wild, but they are different. A cascading wild usually stays on the screen for multiple spins, while the remainder of the winning combination cascades (drops) off the screen. In US online slots, a cascading wild sometimes has a certain number of hits before it also drops off the screen. Three is a standard number of cascading wins before the wild symbol drops off the screen.

 Stacked Wild

Stacked Wilds

The stacked wild is a cross between the expanding and cascading wild features. It expands down the screen to the bottom but does not expand up to the top. For instance, if a stacked wild on a 5×5 screen hits on the middle line, then the stacked wild would expand down to cover the middle, 2nd-lowest, and lowest symbol on the screen. Like the cascading wild, the stacked symbols in USA online slots tend to fall off the screen after creating a winning combination. Stacked wild symbol features often can activate over multiple reels during a bonus game, increasing anticipation and the chances of hitting a winning combination.

 slots cascading reels

Cascading Reels

After a normal slots spin, symbols will stay in place until you spin the reels again. However, cascading reels differ in that symbols from winning payouts disappear, allowing symbols from above to fall into their place.

The benefit to this is that you can create new winning combinations without having to spin again. In some cases, you earn multipliers as more and more wins fall into place.

Obviously, cascading reels add more suspense since you have the opportunity to keep forming wins well after your spin is finished. But keep in mind that you normally have to play all the pay lines in these games to make up for the frequent wins.

 holding and nudging slots reels

Holding and Nudging Reels

These two features were popularized by fruit machines in the UK and are still used in some USA online slots today.

Holding reels allows you to keep one or more entire reels in place while you spin again for bigger prizes. Nudging a reel causes symbols to shift in the reel and potentially create a big win.

Oftentimes, these two features are awarded from a win, but certain games allow you to hold or nudge reels at other points too.

Since holding and nudging give you some degree of control over the reels, they do add a little bit of skill to the equation. However, keep in mind that games with these features normally offer a lower return to play than most slots.

 skill based slots

Skill-based Bonus Rounds

One trend that’s starting to form in the slots industry is more games including skill-based bonus rounds. What’s enticing about this is that your skill has an effect on the return to the player.

Examples of these skill-based bonus rounds involve first-person shooter modes, racing, and flying.

The only catch is that, at the time of this writing, the skill based bonus is a concept that’s slowly filtering into land based and online casinos right now.

 Multiplier slots symbol


The multiplier is not quite as widespread, but it is a popular bonus feature. This multiplies the size of the bonus you receive. If you have 50 coins with a 10x multiplier, you win 500 coins. Multipliers are usually activated with a scatter symbol, but also with the bonus wheel.

 Wild Multiplier

Wild Multipliers

The wild multiplier is a feature offered on Aristocrat Gaming machines like Choy Sun Doa Pokies. What it does is give a player the option to choose either more spins or a bigger multiplier. Let’s use Choy Sun Doa as an example. In that Australian slots game, the player is offered their choice of 5, 8, 10, 15, or 20 free spins. If they choose a high number of spins, their multiplier is lower. If they choose a low number of spins, their multiplier is higher. This way, players can choose between a longer bonus game or a more volatile, shorter game.

 slots with scatter symbols

Scatter Symbols

Scatter symbols are a common feature in USA online slots. These usually are not worth coins, but they activate other features which are worth a lot of coins. It’s called a “scatter” because they can appear anywhere on the screen. You won’t need it to land on a payline to trigger the bonus feature. The main limitation is that most games require 3 or more scatters on the screen to trigger a bonus game or multiplier. Some machines only require 2 or more. Usually, the more scatters you receive, the bigger the advantages. Scatters activate bonus games, multipliers, free spins, or some other advantage.

 Scatter slots paytable

Scatter Pays

Less common is the scatter pay. If you receive a certain amount of scatters, a set amount of coins is won. Players can tell if a game has a scatter pay feature if a pay table marked “Scatter Pays” on the game screen. Some companies called these “Random Instant Wins”.

 Wheel of bonuses

Bonus Wheel

The bonus wheel is given many names by slot machine designers. IGT calls this feature the “Bonus Wheel” or “Wheel of Fortune”. Bally Technologies calls their version the “U-Spin Feature”. Essentially, you spin a virtual wheel with a bunch of different advantages on it: multipliers, free spins, bonus coins, and other options. It’s a fun way to randomize bonuses and the U-Spin Feature seems to be gaining in popularity.

 Pick until Pop feature

Pick Until Pop

The “Pick until Pop” feature is well-known on interactive bonus games. A player is given a grid of options. They might be told to choose a treasure chest, a piece of jewelry, or a type of fruit. When the player picks, a bonus coin amount is shown. The player continues to do this until one of the icons doesn’t have a bonus amount, but instead has a “You Lose” or “pop” icon of some sort. Some games have a single “Pop” icon while others require you to hit a “You Lose” feature three times before the bonus game ends.

 Pick a box feature

Multi-Level Pick a Box

The Multi-Level pick-a-box feature is a variation on the interactive bonus game. Once again, you pick an icon, like you would in the scenario above. Once again, if you pick the wrong symbol, the game ends. In the multi-level bonus game, there is the opportunity to advance to a higher level of the game, if you keep picking the right icon. It’s like leveling up in MMORPGs. The player keeps winning big jackpots until they pop. The multi-level game might have as many as 5 levels. While hard to attain, the 5th level jackpot might be in the 5-figure or 6-figure range.

Those are the most common USA online slots bonus features. Aditionally, you can also find the following options while playing slots.

  • Coin Size: This allows you to adjust the amount that you bet on each pay line. For example, you might be able to switch the coin size from $0.01 to $1.00.
  • Coins per Line: Some slots allow you to put additional coins on each pay line, usually ranging from 1 5 coins per line.
  • Autospin: When turned on, this automatically spins the reels with your designated betting options. Some games let you auto spin the reels for up to 100 spins or more.
  • Max Bet: Quickly play the max number of paylines (and / or other options) by clicking Max Bet.
  • Stop Reels: Want your spin to end early? Just click the Stop button and this will speed up the process.
  • Double Up: Following wins, some slots give you the chance to double up your winnings by playing a mini game. While this sounds fun, these mini-games usually equate to no more than picking whether a coin will be heads or tails, or a card will be red or black.

Over time, new features and options are going to be added to the best online slots in the USA by software designers, in response to player behavior and industry competition.

Popular Online Slots Software

Sometimes, it helps to know about the software company designing the games you play at USA online slots casinos. Below is a brief selection of the land-based and online slot machine developers.

IGT slots software

International Game Technology (IGT)

International Game Technology has more slot machines in North American casinos than any other company. IGT is known for having the biggest progressive jackpots and the most popular slots titles. It also has dozens of licensed slots. IGT has a presence on 5 continents and is a leader in Australia, in particular. IGT also design one of the best online slots in the USA, found in the online and mobile gaming communities.

Bally slots software

Bally Technologies

Bally Technologies long has been IGT’s number one rival in the United States. Bally Technologies began as an American pinball machine manufacturer, but is now a leading USA slots online designer. Like IGT, Bally also has a widespread online presence. Bally Technologies offers its own licensed products with franchises like Michael Jackson, David Copperfield, Grease, and NASCAR.

NetEnt logo

Net Entertainment

NetEnt is a Swedish company known for its 3D interactive slots. Net Entertainment is an online and mobile gaming company only. Its software powers nearly two hundred casinos.

Microgaming slots software


Microgaming is a UK gaming software company. It began operations in 1994 and is therefore one of the oldest Internet software providers. Microgaming has nearly 500 slots games and, at any given time, powers between 250 and 275 online sites. It also formed eCOGRA in the late 1990s to help the online gambling industry police itself.

Playtech logo


Playtech is a rival gaming software company to Microgaming. The Isle of Man-based company calls itself “the world’s largest gambling software and services supplier”. Playtech began operations in 1999 and has hundreds of games in its catalog. Playtech has acquired Aristocrat Leisure and YoYo Games in the past couple of years, so it continues to grow.

Realtime Gaming slots software

RealTime Gaming (RTG)

RealTime Gaming is based out of Costa Rica and licensed in the Netherlands Antilles, but it began in Atlanta, Georgia. The company was sold to Hastings Ltd out of Curacao after the 2006 UIGEA law went into effect. RTG software powers about 75 online casinos, such as Bovada (Bodog) Casino, and provides one of the best online slots in USA. Not all RTG sites are US-friendly, but RTG allows its licensees to decide and most accepts real money American gamblers. RTG is known for video slots like Rudolph’s Revenge and Santa Strikes Back.

To get a thorough insight into the industry, and learn more about the companies that make your favorite slots, check out our Online Casino Software page.

Short History

Old slot machineThe first slot machine was invented in 1895 by Charles Fey, a San Francisco area resident. This gaming machine had a liberty bell as its jackpot symbol, so it became known as the “Liberty Bell” machines. The German immigrant began marketing his Liberty Bell machines to local businesses until San Francisco’s politicians passed gaming laws against them. Charles Fey designed them to pay out in fruit, bubble gums, and prizes instead.

Eventually, California laws became more stringent, so slot machines were outlawed in their home state. In 1931, the state of Nevada approved casino gambling, which gave slot machines a new life. They became a part of the gaming floor, though mechanical slots had only 3 reels and small jackpots, out of necessity. In the post-World War II casino boom, slot machines became a popular form of gambling but did not generate the percentage of revenues they do now.

It took the transition to electronic gaming machines to create the slot machine boom. The first electronic slot machine was released in 1979. By 1981, International Game Technology (IGT) was producing electronic gaming machines (EGMs) for casino floors. With the inception of random number generators (RNGs), the number of reels could be increased. So could the number of symbols on a reel, so the number of potential winning combinations increased exponentially. This allowed for bigger jackpots.

Electronic Slots

As the 1980s progressed, IGT led a revolution in slot machine design. Industry standards like slots clubs and progressive jackpots first appeared. So did the entertainment value of slot machines. This drove tremendous interest in slots row. As casino management began to realize they could offer EGMs with a higher house edge than the table games, casinos invested more money in their slot machine inventory. By the 1990s, games like Wheel of Fortune Slots and MegaBucks Slots were dominating the headlines with their million-dollar jackpots.

Online and Mobile Slots

Mobile Big Win SlotsThese days, slots online represent 65% to 70% of the revenues casinos generate. A wide range of bonus features has been added to the game design while security systems have been improved to protect operators from slot machine cheats. Because they used RNGs for years before their inception, online slots, and mobile slots made an easy transition to the Internet. A wide range of online casino software developers now create the best USA online slots these days.

USA Online Slots FAQ

More than any other casino game, slot machines have more myths and misconceptions. To counter the misinformation, people need to learn the truth about USA slots online. Here are a few common questions that slot machine players ask. I might sound like a spoilsport in these answers, but slot machine gamblers need to hear the cold, hard facts before they play.

What are Online Slots?

How do I play Online Slots?

What types of slot machines are out there?

Is there a difference between online slots and real slots?

Can you win at slots?

What are paylines?

How do I read a slot pay table?

Are slot machine results completely random?

Is a random number generator trustworthy?

What is a scatter?

What are bonus rounds and how do I get them?

What is a progressive slot?

What is the gamble option on some slots?

Why do seasoned gamblers avoid slots?

Is there any slots strategy I can follow?

What is a slots tournament?

What is a class 2 slot and how is it different from a class 3 slot?

Are some slots better to play than others?

Which online slots have the best odds?

Should I join the casino slots club?

What is the difference between a payback percentage and a slot machine hit frequency?

Do you recommend any books on slot machines?

What are some recommended online slots dcasinos deposit methods?